Ginsenosides promote proliferation of chicken primordial germ cells via PKC-involved activation of NF-κB

The effect of ginsenosides on proliferation of chicken primordial germ cells (PGCs) was evaluated and involvement of nuclear factor (NF)KB in the signaling pathway was investigated. PGCs were isolated from the genital ridge of 3.5-4 day embryos and cultured in Medium 199 supplemented with 5% FCS and 10 ng/ml LIE PGCs subcultured on chicken embryonic fibroblast feeder were challenged with ginsenosides alone or in combination with PKC inhibitor H-7 or activator phorbol 12-myristate 13-acetate (PMA) for 24 h. Moreover, the translocation of NF-kB and degradation level of IkB alpha were investigated by Western blot analysis. Results show that PGCs were identified by periodic acid-Schiff, alkaline phosphatase histochemistry as well as c-kit, SSEA-1 and Oct-4 immunocytochernistry. Treatment with ginsenosides at 1-100 mu g/ml significantly increased the number and area of PGC colonies in a dose-dependent manner. However, this proliferating effect was obviously attenuated by combined treatment of H-7 (10(-7) 10(-5) M). Similarly, PKC staining of PGC colonies was more intensive after ginsenosides treatment compared with the control group. In addition, treatment with ginsenosides at 1- 10 mu g/ml stimulated the translocation of NF-KB (p65). However, the NF-icB translocation and the degradation of IKB alpha were significantly blocked by combined treatment with 10(-6) M H-7. These results indicated that ginsenosides promote proliferation of chicken PGCs through activation of PKC-involved NF-KB signaling pathway. (c) 2007 International Federation for Cell Biology. Published by Elsevier Ltd. All rights reserved.